Qt Licensing Debate
This cluster centers on discussions clarifying Qt's licensing model, debating whether a commercial license is needed for proprietary or closed-source applications, and explaining LGPLv3 terms allowing free commercial use with conditions like dynamic linking and source availability for modifications.
Activity Over Time
Top Contributors
Keywords
Sample Comments
Why does Qt need a commercial license? I thought it is available under LGPL?
Qt is LGPL, no need to pay for a license.
Qt is (largely; a couple of optional components are GPL) LGPLv3, so can be used commercially without getting the commercial license.
Licensing issues? The situation around Qt licensing is still not clear, AFAIK.
It's licensed under LGPL 2.1 (or GPL3 if you prefer), so it's free for proprietary/closed-source usage as long as you don't modify Qt itself, or if you at least distribute the source code of the modified Qt binaries. There is also a commercial license if you want support or to be able to modify Qt for a closed-source project, but that requires direct contact with their sales folks afaik.
Isn't Qt still proprietary or semi-proprietary?
Qt is primarily LGPL with some GPL modules, and sells commercial dual-licenses.
What? Qt is mostly LGPL. You don't need a lawyer.
The core of Qt is licensed under LGPL which means you can write and ship proprietary software with it. You just need to dynamically link and provide sources for the Qt libs if a user requests it.
Yeah, but Qt has licensing costs for commercial use...